STANDARD Zoology Mechanism of Breathing MCQ Question
Following diagram indicates the mechanism of breathing. Identify all the parts A, B, C and D correctly
A - Air expelled from lungs; B - Ribs and sternum raised; C - Diaphragm contracted; D - Volume of thorax decreased
A - Air expelled from lungs; B - Ribs and sternum raised; C - Diaphragm relaxed; D - Volume of thorax decreased
A - Air expelled from lungs; B - Ribs and sternum return to original position; C - Diaphragm relaxed; D - Volume of thorax decreased
A - Air entering into lungs; B - Ribs and sternum raised; C - Diaphragm contracted; D - Volume of thorax raised
Correct Answer
Detailed Explanation
A - Air entering into lungs from the region of high pressure (atmosphere) to low pressure (lungs). B - Contraction of external intercostal muscles pulls the ribs and sternum raised. C - Contraction of phrenic muscles of the diaphragm. D - Thoracic cavity increases and pressure decreases.
Found an issue with this question?